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-rw-r--r--sysdeps/x86_64/dl-tls.c53
1 files changed, 53 insertions, 0 deletions
diff --git a/sysdeps/x86_64/dl-tls.c b/sysdeps/x86_64/dl-tls.c
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+++ b/sysdeps/x86_64/dl-tls.c
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+/* Thread-local storage handling in the ELF dynamic linker.  x86-64 version.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifdef SHARED
+/* Work around GCC PR58066, due to which __tls_get_addr may be called
+   with an unaligned stack.  The compat implementation is in
+   tls_get_addr-compat.S.  */
+
+# include <dl-tls.h>
+
+/* Define __tls_get_addr within elf/dl-tls.c under a different
+   name.  */
+extern __typeof__ (__tls_get_addr) ___tls_get_addr;
+
+# define __tls_get_addr ___tls_get_addr
+# include <elf/dl-tls.c>
+# undef __tls_get_addr
+
+hidden_ver (___tls_get_addr, __tls_get_addr)
+
+/* Only handle slow paths for __tls_get_addr.  */
+attribute_hidden
+void *
+__tls_get_addr_slow (GET_ADDR_ARGS)
+{
+  dtv_t *dtv = THREAD_DTV ();
+
+  if (__glibc_unlikely (dtv[0].counter != GL(dl_tls_generation)))
+    return update_get_addr (GET_ADDR_PARAM);
+
+  return tls_get_addr_tail (GET_ADDR_PARAM, dtv, NULL);
+}
+#else
+
+/* No compatibility symbol needed.  */
+# include <elf/dl-tls.c>
+
+#endif